Conventionally, there has been an input device that is provided with a touchpad on which the user performs an operation by a finger, to input a setting value for operating a predetermined device, where an input operation can be performed by a contact of the finger at a single spot or at multiple spots on the surface of the touchpad, and includes an adjuster unit to adjust the setting value or a change width for changing the setting value by a single finger operation, depending on increase or decrease in the contacting area on the surface while the finger operation is being performed (see, for example, Patent Document 1).